Recently manufactured vehicles are equipped with a special system called On-Board Diagnostic II (OBD II). OBD II monitors all engine and drive train sensors and actuators for shorts, open circuits, lazy sensors and out-of-range values as well as values that do not logically fit with other power train data. Thus, OBD II keeps track of all of the components responsible for emissions and when one of them malfunctions, it signals the vehicle owner by illuminating a Maintenance Indicator Lamp (MEL), such as a check engine indicator. It also stores Diagnostic Trouble Codes (DTCs) designed to help a technician find and repair the emission related problem. OBD It also specifies the means for communicating diagnostic information to equipment used in diagnosing, repairing and testing the vehicle.
An illuminated MIL means that the OBD II system has detected a problem that may cause increased emissions. A blinking MIL indicates a severe engine misfire that can damage the catalytic converter. The MEL is reserved for emission control and monitored systems and may not be used for any other purpose. The “Check Engine,” “Service Engine Soon” or other “engine symbol” message is typically used as an MEL indicator.
Although the MEL is helpful to a driver in that it lets the driver know that there is an issue with the vehicle, the driver, however, may not know if the problem is serious or not. Accordingly, it is desirable to provide a method and apparatus that provides recommendations to the driver regarding the stored code (DTC).